The invention relates to a crawler track, especially for tracked vehicles where the track includes individual articulated links interlocked with each other.
Heavy demands are made upon tracked vehicles, in particular upon heavy armoured vehicles suitable for manoeuvring under differing conditions. In this connection there is a requirement for lower weight, less power, lower vehicle height and thus for a shallower depth of track. All these factors are to a greater or lesser degree affected by each other and not least by the manner in which the track is constructed. It is thus desirable to achieve lower manufacturing and repair costs, simplified maintenance and a useful working life.
The design of track links has a not inconsiderable effect on the vehicle's weight, power requirements and size. The worse these characteristics are, the less favourable will be the vehicle's ability to operate over very uneven terrain and soft surfaces.
Many types of track have been devised and are represented amongst those selected for armoured vehicles. It has been demonstrated that a tank of about 50 tons requires a power unit of about 750 kw., and it is apparent that a tank with such a powerful engine will be large and heavy and have limited capabilities on difficult ground and on heavy going on wet clay, snow, etc., which cannot take heavy loads. The reason for the high power requirement is to a great degree related to the design of the track and its links (track plates) which absorb a noticeable amount of energy. The rubber sole below the plates becomes hot and absorbs energy because it offers too great a resistance and inadequate transmission of stress between the plates. Two adjacent plates are connected by a bolt which means that the plates are subjected to a flexing movement which consumes energy. The flexing has further importance in causing the drive wheels to absorb energy as they are not operating on a plane surface. A further disadvantage with the design is that two rubber cushions in principle cover the whole length and breadth of the track plates and thus the track is too smooth and takes a poor grip on clay surfaces compared with a surface with a tread, and exerts poor traction in wet conditions. Beacuse each track plate has a high rubber sole, and a single track bolt is used between each track plate, the latter become thick and heavy which results in a high heavy vehicle. The height of the rubber sole and thus its greater resistance has a negative side effect; the track plates "slap" during driving, this is to say the vehicle's movement is jerky. The thickness of rubber sole under the track plates prevents the drive teeth from gripping ice or packed snow. This type of track plate and its connecting portion is constructed in one piece which results in high spares and repair costs as it is necessary to change the whole track plate when damaged, for example when the track bolt socket has worn. These sockets are of rubber, vulcanised to the track plate body. The life of these rubber sockets is short and instead of re-rubbering them, the whole track plate is replaced.